One-piece tanks are available in standard sizes from 45 to 100,000 litres. Special sized tanks can also be made up to a maximum width of 3000mm, height of 2500mm, and length up to 14000mm.

They are suitable for cold water storage up to 30°C. Drayton also offers tanks that can hold water up to 70°C constant (F&E tanks) and up to 100°C (chemical tanks).

They have a smooth interior surface for easy cleaning and are resistant to bacteria. An inspection hatch is supplied on all tanks over 1000 litres.

Standard one-piece tanks are available plain and pre-insulated. Pre-insulated tanks have CFC-free insulation encapsulated in the tank. Standard insulated wall thickness is 25mm thick, with up to 100mm available.

No joints or sealants are required on site, and there are no expensive erection or assembly costs compared with panel / sectional tanks.

The new Water Regulations (previously byelaw 30) require that a cistern storing wholesome water should be insulated against heat and frost with suitably sized overflow / warning pipes, The overflow fitting should be a minimum twice the size of the inlet into the tank.